ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 53 



with a thin diaphragm. Broch also re-establishes Allman's genus Lic- 

 torella : Lafoeidas with more or less bell-like kydrothecse, which have a 

 strongly developed diaphragm : the hydrocaulus is upright, and regularly 

 branched ; nematophores are absent ; the gonangia are aggregated in a 

 scape. There is one species, Lictorella pi/mala (G. 0. Sars), from deep 

 water in the North Sea and the Bay of Biscay. 



Feeding Reactions of the Rose-coral.* — F. W. Carpenter has in- 

 vestigated the reactions which follow the stimulation of the rose-coral 

 polyp of the genus Tsophyllia by means of nutrient substances. When 

 concentrated meat extract is applied to the oral disk of the polyp, the 

 disk is drawn downwards by the contraction of the retractor muscles of 

 the mesenteries, and the margin of the oral surface is folded inward over 

 the disk by the action of a well-developed sphincter muscle. Mean- 

 while the stomodaeum is everted, and the mesenterial filaments are 

 •-xtruded both through the mouth and through temporary apertures in 

 the oral disk. The tentacles react quickly to contact stimulation, and 

 affix the object which touches them to their distal ends, which are 

 heavily loaded with nematocysts. When the end of a tentacle is chemi- 

 cally stimulated with meat extract, the retractor muscles of the polyp 

 contract. Carmine grains dropped on the oral surface of an expanded 

 polyp are transferred by ciliary action to the periphery. When the 

 particles of carmine have previously been soaked in meat juice, the cilia 

 usually continue to beat in an outward direction ; occasionally, how- 

 ever, they reverse their effective strokes. The chief function of the 

 cilia seems to be that of keeping the oral surface clean. When a polyp 

 is fed with plankton, the small organisms are caught by the tentacles, 

 the oral disk sinks and the marginal zone folds inward until it com- 

 pletely roofs over the tentacles and the depressed oral disk. Into the 

 superficial chamber thus formed, the stomodaeum and mesenterial fila- 

 ments project, and here the mesenterial filaments, which are the 

 digestive organs of the polyp, probably digest and ingest or absorb 

 the captured plankton, little of which seems to find its way into the 

 reduced gastrocoeliac cavity. Extra-ccelenteric digestion apparently 

 takes place, therefore, in the rose-coral polyps. There is experimental 

 evidence of the transmission of impulses of at least a nervoid char- 

 acter from ectodermal receptor cells through the mesogloea to endo- 

 dermal effectors (muscles). This transmission is not confined to a 

 single polyp, but may pass from one polyp to another. It is known 

 that branching cells (so-called " connective-tissue " cells) occur in the 

 mesogloea of Isophyllia. These extend from the ectoderm to the endo- 

 derm, and so have the topographical relations of adjustor cells, placing 

 the receptor in communication with the effector. Notwithstanding 

 absence of exact information as to the origin, mutual relationships, and 

 functions of these cells, it is suggested that future studies may show 

 them to be the primitive synaptic neurones. • 



Kodioides.f — ('has. L. Walton describes Kodioides borleyi sp. n. from 

 20 fathoms close to the Dutch coast. The previously known species of 



* Proc. Amer. Acad., xlvi. (1910) pp. 149-62 (1 pi.), 

 t Journ. Marine Biol. Assoc, ix. (1910) pp. 85-7. 



